This proposal requests funds to establish a Center of Excellence in Molecular Hematology at the University of Utah. The proposed Center would include five research groups: Molecular Regulation of Iron and Heme Metabolism; Cell Adhesion; Complement Regulation - Paroxysmal Nocturnal Hemoglobinuria; Cell Differentiation; and Cytokines and Hematopoiesis. Research projects from the first four of these groups are included in this application. Two core laboratories are proposed: a Stem Cell Core and an Homologous Recombination Core. A Pilot Project Program is proposed and four potential pilot projects are described. Numerous University core facilities which will interact with the Center are described, as are other interactive programs at the Health Sciences Center.